参数资料
型号: MAX4949ELA+T
厂商: Maxim Integrated Products
文件页数: 8/10页
文件大小: 0K
描述: IC CTLR OVP W/FET 8.90V 8-UDFN
产品培训模块: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
标准包装: 2,500
类型: 过压保护控制器
应用: 手机,数码相机,媒体播放器
安装类型: 表面贴装
封装/外壳: 8-WFDFN
供应商设备封装: 8-uDFN(2x2)
包装: 带卷 (TR)
GP GATE Drive
When the input voltage goes above ground, GP pulls
low and turns on the pFET. An internal clamp protects
the pFET by ensuring that the GP to IN voltage does not
exceed 19V (max) when the input (IN) rises to +28V.
Undervoltage Lockout (UVLO)
The MAX4944L/MAX4945L/MAX4946/MAX4949 have a
2.45V (typ) undervoltage-lockout threshold (VUVLO),
while the remaining devices have a 4.15V (typ) VUVLO
threshold. When VIN is less than VUVLO, ACOK is high
impedance.
Overvoltage-Lockout Thresholds (OVLO)
The MAX4943 has a 7.4V (typ) overvoltage threshold
(VOVLO), the MAX4944_ has a 6.35V (typ) VOVLO
threshold, the MAX4945_ has a 5.80V (typ) VOVLO
threshold, the MAX4946 has a 4.56V (typ) VOVLO
threshold, and the MAX4949 has a 8.90V (typ) VOVLO
threshold. When VIN is greater than OVLO, ACOK is
high impedance.
ACOK
ACOK is an active-low, open-drain output that asserts
low when VUVLO < VIN < VOVLO for the 30ms (typ) peri-
od. Connect a pullup resistor from
ACOK to the logic
I/O voltage of the host system. During a short-circuit
fault,
ACOK may deassert due to VIN not being in the
valid operating voltage range.
Thermal-Shutdown Protection
The MAX4943–MAX4946/MAX4949 feature thermal-shut-
down circuitry. The internal switch turns off when the junc-
tion temperature exceeds +175°C (typ) and immediately
goes into a fault mode. The device exits thermal shut-
down after the junction temperature cools by 40°C (typ).
Applications Information
IN Bypass Capacitor
For most applications, bypass IN to GND with a 1F
ceramic capacitor as close as possible to the device to
enable ±15kV (HBM) ESD protection on the pin. If
±15kV is not required, there is no capacitor required at
IN. If the power source has significant inductance due
to long lead length, take care to prevent overshoots
due to the LC tank circuit and provide protection if nec-
essary to prevent exceeding the +30V absolute maxi-
mum rating on IN.
Reverse Polarity Protection
The optional external pFET can provide reverse polarity
protection down to -28V (for a 30V pFET), if the protect-
MAX4943–MAX4946/MAX4944L/MAX4945A/MAX4945L/MAX4949
Overvoltage-Protection Controllers with
Internal FET
_______________________________________________________________________________________
7
SWITCH ON
SWITCH OFF
CURRENT
THROUGH
SWITCH
ILIM
tOFF
tRETRY
SWITCH ON
Figure 3. Autoretry Timing Diagram
CHARGE-CURRENT-
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
Cs
100pF
RC
1M
Ω
RD
1.5k
Ω
HIGH-
VOLTAGE
DC
SOURCE
DEVICE
UNDER
TEST
Figure 4. Human Body ESD Test Model
IP 100%
90%
36.8%
tRL
TIME
tDL
CURRENT WAVEFORM
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
Ir
10%
0
AMPERES
Figure 5. Human Body Current Waveform
相关PDF资料
PDF描述
MAX4960EUB+T IC CTLR HI VOLTAGE OVP 10-MSOP
MAX4959EUB+T IC CTLR HI VOLTAGE OVP 10-MSOP
MAX4960ELB+T IC CTLR HI VOLTAGE OVP 10-UDFN
MAX4944BELA+T IC CTLR OVP W/FET 6.35V 8-UDFN
MAX4945BELA+T IC CTLR OVP W/FET 5.80V 8-UDFN
相关代理商/技术参数
参数描述
MAX494CPD 功能描述:运算放大器 - 运放 uPower Single-Supply Rail-Rail RoHS:否 制造商:STMicroelectronics 通道数量:4 共模抑制比(最小值):63 dB 输入补偿电压:1 mV 输入偏流(最大值):10 pA 工作电源电压:2.7 V to 5.5 V 安装风格:SMD/SMT 封装 / 箱体:QFN-16 转换速度:0.89 V/us 关闭:No 输出电流:55 mA 最大工作温度:+ 125 C 封装:Reel
MAX494CPD+ 功能描述:运算放大器 - 运放 uPower Single-Supply Rail-Rail RoHS:否 制造商:STMicroelectronics 通道数量:4 共模抑制比(最小值):63 dB 输入补偿电压:1 mV 输入偏流(最大值):10 pA 工作电源电压:2.7 V to 5.5 V 安装风格:SMD/SMT 封装 / 箱体:QFN-16 转换速度:0.89 V/us 关闭:No 输出电流:55 mA 最大工作温度:+ 125 C 封装:Reel
MAX494CSD 功能描述:运算放大器 - 运放 uPower Single-Supply Rail-Rail RoHS:否 制造商:STMicroelectronics 通道数量:4 共模抑制比(最小值):63 dB 输入补偿电压:1 mV 输入偏流(最大值):10 pA 工作电源电压:2.7 V to 5.5 V 安装风格:SMD/SMT 封装 / 箱体:QFN-16 转换速度:0.89 V/us 关闭:No 输出电流:55 mA 最大工作温度:+ 125 C 封装:Reel
MAX494CSD+ 功能描述:运算放大器 - 运放 uPower Single-Supply Rail-Rail RoHS:否 制造商:STMicroelectronics 通道数量:4 共模抑制比(最小值):63 dB 输入补偿电压:1 mV 输入偏流(最大值):10 pA 工作电源电压:2.7 V to 5.5 V 安装风格:SMD/SMT 封装 / 箱体:QFN-16 转换速度:0.89 V/us 关闭:No 输出电流:55 mA 最大工作温度:+ 125 C 封装:Reel
MAX494CSD+T 功能描述:运算放大器 - 运放 uPower Single-Supply Rail-Rail RoHS:否 制造商:STMicroelectronics 通道数量:4 共模抑制比(最小值):63 dB 输入补偿电压:1 mV 输入偏流(最大值):10 pA 工作电源电压:2.7 V to 5.5 V 安装风格:SMD/SMT 封装 / 箱体:QFN-16 转换速度:0.89 V/us 关闭:No 输出电流:55 mA 最大工作温度:+ 125 C 封装:Reel